In a sport of this kind, when the skier performing the skating step finishes his propulsion motion on one of the skis, he transfers his weight onto the other, opposite ski and brings the first ski back to the level of the second.
This return movement is different depending on:
speed, thus the step used. In fact, the slower the speed the higher the frequency of the skating step, and thus the less time the skier has to pull his ski back. For this reason, the slower the speed, the less the skis are brought back into a parallel position, and the more the skier preserves a substantial divergence between the two skis. PA1 the slope encountered. In fact, the skier must pull his ski back in the most parallel fashion possible in relation to the slope, in order not to raise the ski excessively. The inclination of the ski during the return movement thus depends on the slope encountered (a fact which makes the return movement particularly demanding and difficult on steep slopes).
These various findings have led to study of the problem of the return movement of the ski when performing the skating step.
The criteria chosen to evaluate the problem include the release of the ski, the control of the ski in the air, and the replacement of the ski on the snow.
This study revealed, in fact, that when the ski is released, the front end, or tip, of the ski tends to catche in the snow, thereby causing the real problem, namely the longitudinal angular control of the ski in the quasi-static phase, i.e., when it is in the air.
Once the problem was stated in this way, it was also found that one consequence for the skier Consisted in the need to increase the contraction of the front leg muscle so as to lift the ski and prevent the tip from catching in the snow during the return-motion phase of the ski. This is especially harmful to the skier, because he should, to the contrary, be able to use this phase to relax to the maximum extent the muscles of the leg in question, since this is supposed to be a resting, not a propulsion, phase.